It is known (see, for example, French Pat. No. 909,611) to provide such a roller coaster with a U-shaped track from whose lowest point a vehicle is hoisted to the highest point whence it descends with sufficient acceleration to pass through a vertical loop near the bottom of the slope, followed by a rising slope which it ascends before returning to its starting position. Such an amusement ride is highly thrilling, yet the delay involved in hoisting the vehicle to the peak of its track reduces the available riding time in comparison with, say, a conventional figure-eight ride of the same overall cycle length.